Patricia Campatelli fought an uphill battle to get elected Suffolk County register of probate in 2012. And she may not have stopped fighting.

The political newcomer was placed on administrative leave for four days last month while court officials investigated allegations that she punched an employee in the face during an argument after a Christmas party in downtown Boston.

Campatelli, who has faced other accusations of belligerent behavior since beginning her upset campaign for register in 2012, was allowed to return to work after court officials could not substantiate the employee’s allegation, according to a court spokeswoman.

But the alleged victim, a longtime case coordinator in Campatelli’s office named Timothy Perry, has not returned to work, aside from one day when a co-worker said he had a visible bruise or laceration on his lip. It is unclear whether Perry’s absence is related to the incident, but one court official said Perry initially was extremely upset about the alleged assault, though he has not filed a criminal complaint.

“It had to be a ‘he said, she said’ kind of thing,” said a third person familiar with the holiday season altercation, which Perry alleged took place in a car in which he and Campatelli were passengers riding home after stops at two downtown restaurants and bars.

Campatelli declined to comment, referring all questions to trial court spokeswoman Jennifer Donahue, who confirmed that Campatelli was briefly placed on paid leave while court officials investigated the allegation.

“The investigation determined that the allegation against the register was not supported,” Donahue said in a statement.

Campatelli, who narrowly won election despite being outspent six-to-one by her opponent, is paid $110,075 a year to manage court cases involving family issues such as divorces, child custody and support, and distribution of assets after death.

The East Boston resident, a former Probation Department manager who has also worked as a substitute teacher and social worker, followed an unorthodox course from the start: She asked Secretary of State William F. Galvin to swear her into office at a bar on New Year’s Eve, 2012.

But Campatelli has encountered other controversies since she began running for the obscure post.

For several months during the 2012 primary campaign for register, inflammatory messages appeared on Campatelli’s personal and campaign Facebook pages, including accusations that specific individuals were unfaithful to their wives, had contracted sexually transmitted diseases, or were secretly homosexual.

“Ur man is cheating on u,” said a posting on Campatelli’s campaign Facebook page in September 2012 in response to a woman who had criticized her.

One target of the postings, a former Campatelli house guest named Robert Burnett of Lynn, was so incensed that he sought a restraining order against her, though a judge turned it down, saying the postings were protected under the First Amendment.

Campatelli denied to the Globe in 2012 that she had posted any offensive messages, noting that up to 20 people at one point were allowed to post messages on her campaign Facebook page. She subsequently limited access so that only she could post messages in her name and apologized to anyone who was offended.

“I know what libel and slander is,” Campatelli explained in September 2012. “Now why would I do that a week before the election?”

A few weeks after her surprise victory over Boston city councilor Salvatore LaMattina — 15,817 to 15,184 — on Sept. 6, 2012, Campatelli was involved in a loud altercation at Ecco restaurant in East Boston with LaMattina supporters, prompting one witness to file a police complaint.

“She was screaming,” said Nancy LoConte of East Boston, who witnessed the Sept. 22, 2012, incident. “She was yelling at people she didn’t even know.”

LoConte, who campaigned for LaMattina, said she was eating with about 10 other people, including Representative Carlo P. Basile, another LaMattina supporter. Basile confirmed to the Globe at the time that Campatelli had shouted at the group, saying he believed it was because the group had not supported her for register of probate.

LoConte, who said she had never spoken to Campatelli previously, said that Campatelli mistakenly referred to her as Denise during the Ecco altercation and, at one point appeared ready to hit her until someone intervened, according to the police report. LoConte told police that Campatelli kept yelling at customers, knocking over a table and several glasses in the process.

“She swore at me; she told me I was a sellout; she told me all these things,” LoConte told the Globe in September 2012. “She just kept badgering.”

Campatelli did not return calls for comment at the time. In response to requests for an interview about the incident with Perry, she referred questions to the Administrative Office of the Trial Court.

Perry, who has worked for the court since 1997, could not be reached for comment on the incident with his boss. However, several people familiar with the fracas helped reconstruct the sequence of events.

After a mid-December Christmas party at Hennessy’s in downtown Boston, some of the partygoers went to Prezza in the North End for an afterparty, according to one person who attended the Hennessy’s gathering. Later, a friend of Campatelli gave Campatelli and Perry a ride home, and the two began to argue, said someone who spoke directly to Perry about the incident.

Perry told this person that Campatelli, who was sitting in the front seat, turned around to where Perry was sitting in the back and punched him in the face. It was unclear what the two were arguing about, said the person who spoke to Perry. A second person familiar with Perry’s allegations confirmed that the altercation happened in the car.

The day after the incident, Perry called in sick, according to a colleague at the Registry of Probate. The next day, a Friday, he showed up for work with a visible bruise on his lip, said the co-worker. The following Monday, Campatelli was placed on paid leave by the chief justice of the probate and family court, Angela M. Ordonez, and Perry did not come to work.

After four days’ leave, Ordonez allowed Campatelli to return to work, but Perry still has still not returned, said co-workers at the Registry.

Court officials did not disclose whether they interviewed the third person in the car on the night of the altercation, who was not a court employee. In the end, Donahue said further investigation of the incident was “unwarranted.”